1 / 40

Georgia Performance Standards: Compare and contrast cell reproduction (mitosis) in eukaryotes and prokaryotes

CELL Reproduction (Division). Georgia Performance Standards: Compare and contrast cell reproduction (mitosis) in eukaryotes and prokaryotes. Essential Questions: EQ: Why is mitosis necessary in cell reproduction? EQ: What happens when mitosis goes wrong?. Cellular Reproduction. Chapter 9.

marvela
Download Presentation

Georgia Performance Standards: Compare and contrast cell reproduction (mitosis) in eukaryotes and prokaryotes

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CELL Reproduction (Division) Georgia Performance Standards:Compare and contrast cell reproduction (mitosis) in eukaryotes and prokaryotes Essential Questions: EQ: Why is mitosis necessary in cell reproduction? EQ: What happens when mitosis goes wrong?

  2. Cellular Reproduction Chapter 9 What’s wrong with big cells? • As the cell grows, its volume increases much more rapidly than the surface area. • The cell might have difficulty supplying nutrients and expelling enough waste products.

  3. Ratio of Surface Area to Volume in Cells Section 10-1 Cell Size Surface Area (length x width x 6) Volume (length x width x height) Ratio of Surface Area to Volume Review:The larger a cell becomes, the more demands the cell places on its DNA and the more trouble the cell has moving enough nutrients and wastes across the cell membrane. Go to Section:

  4. Cellular Reproduction Chapter 9 Transport of Substances is slow for big cells • Substances move by diffusion or by motor proteins. • Diffusion over large distances is slow and inefficient. • Small cells maintain more efficient transport systems.

  5. Cellular Reproduction Chapter 9 Cellular Communications are compromised in big cells • The need for signaling proteins to move throughout the cell also limits cell size. • Cell size affects the ability of the cell to communicate instructions for cellular functions.

  6. Cell Division • What do you think would happen if a cell were simply to split into two, without any advance preparation? • Would each daughter cell have everything it needed to survive?

  7. Every cell must first copy its genetic information before cell division begins. • Each daughter cell then gets a complete copy of that information. • Cell division is called mitosis • Each cell has identical DNA

  8. In eukaryotic cells, the genetic information is carried by chromosomes. Chromosomes are made up of DNA and protein. At the beginning of cell division, each chromosome consists of two identical “sister” chromatids. Each pair of chromatids is attached at an area called the centromere. Cell Division

  9. Cellular Reproduction Chapter 9 The Cell Cycle • Cell division prevents the cell from becoming too large. • The cell reproduces so that you grow and heal certain injuries. • Cells reproduce by a cycle of growing and dividing called the cell cycle.

  10. During the cell cycle, a cell grows, prepares for division, and divides to form two daughter cells, each of which then begins the cycle again. The Cell Cycle

  11. Cellular Reproduction Chapter 9 9.1 Cellular Growth • Interphase is the stage during which the cell grows, carries out cellular functions, and replicates. • Mitosis is the stage of the cell cycle during which the cell’s nucleus and nuclear material divide. • Cytokinesisis the method by which a cell’s cytoplasm divides, creating a new cell.

  12.  The Cell Cycle Section 10-2 G1 phase M phase S phase G2 phase Go to Section:

  13. Cellular Reproduction Chapter 9 9.1 Cellular Growth The Stages of Interphase • The first stage of interphase, G1 • The cell is growing, carrying out normal cell functions, and preparing to replicate DNA.

  14. Cellular Reproduction Chapter 9 9.1 Cellular Growth The Second Stage of Interphase, S • The cell copies its DNA in preparation for cell division.

  15. Cellular Reproduction Chapter 9 9.1 Cellular Growth The Third Stage of Interphase, G2 • The cell prepares for the division of its nucleus.

  16. Prophase Metaphase Anaphase Telophase Mitosis: Four Stages

  17. Cellular Reproduction Chapter 9 9.2 Mitosis and Cytokinesis The Stages of Mitosis • Prophase • The cell’s chromatin tightens. • Sister chromatids are attached at the centromere. • Spindle fibers form in the cytoplasm.

  18. Cellular Reproduction Chapter 9 9.2 Mitosis and Cytokinesis • The nuclear envelope seems to disappear. • Spindle fibers attach to the sister chromatids.

  19. Cellular Reproduction Chapter 9 9.2 Mitosis and Cytokinesis Metaphase • Sister chromatids are pulled along the spindle apparatus toward the center of the cell. • They line up in the middle of the cell.

  20. Cellular Reproduction Chapter 9 9.2 Mitosis and Cytokinesis Anaphase • The microtubules of the spindle apparatus begin to shorten. • The sister chromatids separate. • The chromosomes move toward the poles of the cell.

  21. Cellular Reproduction Chapter 9 9.2 Mitosis and Cytokinesis Telophase • The chromosomes arrive at the poles and begin to relax. • Two new nuclear membranes begin to form and the nucleoli reappear. • The spindle apparatus disassembles.

  22. Cytokinesis • As a result of mitosis, two nuclei—each with a duplicate set of chromosomes—are formed, usually within the cytoplasm of a single cell. • Cytokinesis: the division of the cytoplasm itself, ends mitosis. • Cytokinesis usually occurs at the same time as telophase.

  23. In most animal cells the cell membrane is drawn inward until the cytoplasm is pinched into two nearly equal parts. Each part contains its own nucleus and cytoplasmic organelles. In plants cells a structure known as the cell plate forms midway between the divided nuclei The cell plate gradually develops into a separating membrane. A cell wall then begins to appear in the cell plate. Cytokinesis

  24. Cellular Reproduction Chapter 9

  25. M phase (Mitosis) Interphase G1 phase S phase G2 phase Prophase Metaphase Anaphase Telophase Concept Map Section 10-2 Cell Cycle includes Cytokinesis is divided into is divided into Go to Section:

  26. Bacteria and Viruses Prokaryote (Bacteria) Structure • Prokaryotes are microscopic, unicellular organisms. • They have some characteristics of all cells, such as DNA and ribosomes. • Lack a nuclear membrane and other membrane-bound organelles

  27. Cell Division • In prokaryotes, the cell first replicates its genetic information before cell division begins. Then the cell splits into two parts.

  28. Bacteria and Viruses Reproduction of Prokaryotes: 2 Types • Binary Fission: Division of a cell into two genetically identical cells • Conjugation: Two prokaryotes attach to each other and exchange genetic information.

  29. Every cell must first copy its genetic information before cell division begins. Cell division is called mitosis Mitosis produces two genetically identical daughter cells with 2 sets of chromosomes (diploid) Mitosis Summary

  30. Checkpoint Questions 1. Name the 3 main events of the cell cycle. 2. Describe what happens during each of the four phases of mitosis. 3. Describe what happens during interphase. 4. What are chromosomes made of? 5. Compare and contrast how prokaryotic and eukaryotic cells divide? 6. Compare and contrast cytokenesis in plant and animal cells.

  31. What happens when mitosis goes wrong?

  32. Cellular Reproduction Chapter 9 Normal Cell Cycle • Different cyclin/CDK combinations signal other activities, including DNA replication, protein synthesis, and nuclear division throughout the cell cycle.

  33. Cellular Reproduction Chapter 9 Quality Control Checkpoints • The cell cycle has built-in checkpoints that monitor the cycle and can stop it if something goes wrong. • Spindle checkpoints also have been identified in mitosis.

  34. Cancer cells can kill an organism by crowding out normal cells, resulting in the loss of tissue function. Chapter 9 9.3 Cell Cycle Regulation Abnormal Cell Cycle: Cancer • Cancer is the uncontrolled growth and division of cells.

  35. Cellular Reproduction Chapter 9 Causes of Cancer • The changes that occur in the regulation of cell growth and division of cancer cells are due to mutations. • Various environmental factors can affect the occurrence of cancer cells.

  36. Cellular Reproduction Chapter 9 Apoptosis • Programmed cell death • Cells going through apoptosis actually shrink and shrivel in a controlled process.

  37. Cellular Reproduction Chapter 9 9.3 Cell Cycle Regulation Stem Cells • Unspecialized cells that can develop into specialized cells when under the right conditions

  38. Cellular Reproduction Chapter 9 Embryonic Stem Cells • After fertilization, the resulting mass of cells divides repeatedly until there are about 100–150 cells. These cells have not become specialized.

  39. Cellular Reproduction Chapter 9 Adult Stem Cells • Found in various tissues in the body and might be used to maintain and repair the same kind of tissue • Less controversial because the adult stem cells can be obtained with the consent of their donor

  40. Stem Cell Movie: http://learn.genetics.utah.edu/content/tech/stemcells/sctypes/

More Related